I just received my new Colt 6400C M4 A3 carbine. I'd like to add an Aimpoint CompM2 but I need some guidance on a suitable mounting ring and backup iron sight.

Originally I was going to simply buy Aimpoint's stock ring with spacer and mount the sight on the receiver rail, but there are a bunch of different options available from GG&G and ARMS. Can someone point me in the direction of the most durable solution? Price is a consideration but I'll pay more if one product is clearly more durable than another.

Next, what about a flip-up iron sight for a backup that is tall enough to mount directly on the receiver rail?

Thanks in advance for your help. I tried a search but for some reason the search page comes up blank for me. Please accept my apology if these questions have already been covered ad nauseum.

Hello CJan_NH, their are several options for mounting the Aimpoint to your flattop. The most popular setup would probably be an ARMS #22M68 with either a full spacer or the new Cantilever. As far as BUIS go, the ARMS #40 is an excellent BUIS. You could go with an ARMS #38 which gives you a BUIS and you can mount the #22M68 on it without the spacer. Good luck with your choices..
C4
[email]gandrtactical@verizon.net[/email]

There's the ARMS SIR route, w/#22M68:
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=1367[/img]
ARMS 38EX, w/#22M68:
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=6198[/img]
The #38 comes w/ the ARMS #40, extra on the SIRs:
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=1368[/img]
Or go the EOTech route and #40, which is a bit cheaper, as EO mounts directly to the flat-top:
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=16333[/img]
These are my favorite choices, btw the #38 comes in SuperEX length, check w/ Legal Transfers, CMMG or MSTN on the EE or Donnie here: [url]www.sableco.net[/url], I've dealt w/ them all and their all top notch....
Mike
BTW - if your NOT gonna need a NV device you'll save a few bucks w/ the ML2 over the M2....

I like the ARMS 22M68 Cantilever mount and #40 BUIS. Rock solid, and the 40 is THE best back up sight, having tried them all, IMHO.
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=12665[/img]
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=12668[/img]

If your search had worked I think you would have found that the Arms #22M68 and #40 BUIS are by far the most recommended. I have that set up on my M4 and it works great and is sturdy as can be.
Good luck.

Excellent. Thanks for the help guys, I'll buy an ARMS #22M68 and an ARMS #40 BUIS.
Judging by the pics that some of you posted, it looks like the #40 BUIS mounts right to the receiver rail without the need for an additional spacer. If I use a #22M68 directly on the rail will I need the small spacer that goes directly under it to bring the Aimpoint up high enough to zero it with the irons? In the interest of keeping it simple (and cost effective), I don't think I want a swan sleeve or a SIR system. Ideally I'd like to simply bolt the Aimpoint and backup iron directly onto the receiver. Can I do this with the #22M68 spacer?